The use of sensor networks to detect, identify and track moving targets, particularly vehicles, is one that has been increasingly developed. Moving targets such as vehicles are often easy to identify due to the large seismic, magnetic or acoustic signals presented to the sensors that can easily distinguish them from the background noise. The effective range for sensors targeting moving vehicles as a result can be very large and thus only a few sensors are needed to cover a wide area. However, moving targets such as humans, horses or deer or the like provide signals that are often very small and difficult to distinguish from the surrounding background noise. Therefore, the effective range for sensors targeting humans, horses and deer can be very small.
Providing wide area sensor networks targeted for humans, horses and deer is currently problematic. To track targets that present small signals to the sensors requires a dense deployment of sensors to cover a wide area due to the limited range of each sensor. Each sensor must be small for reasons of cost and ease of deployment, and in some cases, the sensors need to be hidden from the targets. However, limiting the size of the sensors requires that the sensors provide the necessary communications to a processor unit at a low bandwidth and using a low amount of power.
For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the area of sensor networks for a low cost method of sensing moving targets such as humans, horses and deer or the like over a wide area using limited power and bandwidth.